change database from latin1 to UTF8

[emath]

it didnt worked for me !
(i had many problems, after solveing them , i had a collation mix problem, so i converted all the collation also, and then after i successfully logged in my admin cp i didnt see hebrew , only english and gibbreish - although i used UTF8 encoded.. )

my db size is about 220MB .

anyone can make it clear once and for all how to do the convert?

so many people are looking for this .....